Douglas Bag Exam Flashcards
What is the equipment involved?
\+ Douglas bag rack 4 bad \+ Mouth piece \+ 3 way valve \+ Blue paper \+ Nose clip \+ Stop watch - to time the collection period \+ Breathing tube \+ Monark cycle ergometer \+ Heart rate monitor \+ RPE scale - (Rating of perceived exertion) - Borg scale - 6-20 \+ Vacuum pump and extraction tube to empty the douglas bag before use \+ Environmental stations \+ Stadiometer - height \+ Body mass scales - weight \+ Gas analysis station
Pre testing prep:
\+ Explain whats involved \+ Consent \+ PARQ \+ Witness Sign PARQ \+ Measurements: Participants- Weight, Height, BMI. Room - Temp, Pressure, Humidity
What you are testing and why?
Measures gas exchange and substrate usage, in submaximal range.
By measuring the volume of air we breathe in and out in 1 min, and the composition of oxygen and carbon dioxide in that breath sample we can determine what substrates are being utilised for energy provision – this is called indirect calorimetry.
Define submaximal exercise.
Submaximal performance testing is a way of estimating either VO2 max or “aerobic fitness” in sports medicine. The test protocols do not reach the maximum of the respiratory and cardiovascular systems. Submaximal tests are used because maximal tests can be dangerous in individuals who are not considered normal healthy subjects and for elite athletes maximal tests would disrupt training load balance.
How can you determine Submax in a particpant?
220-age
50-70% Heart rate reserve
Whats the basic exercise protocol and gas sampling?
Stage 1: Start exercise 0-4 mins. 4-5 mins collect air. 5th minute add more weight.
Stage 2: exercise 5-9. 9-10 collect air. Finish test.
How do you calibrate the gas machine?
+ Switch on the system to warm up
+ Connect gas line and open the cylinder and regulator value 1000cc/min
+ Set O2 low and entre calibration - 2 mins to o2 0.00%
+ Repeat co2 low until stabilised
+ Connect gas line and open the cylinder and regulator value 1000cc/min
+ High span gas o2 high - gas 2 mins target 16.08%
+ Co2 high - 5.03%
+ Sample ambient air 2mins - make note o2 and co2 values to calculate vo2 and vco2
+ 02 = around 20%
+Co2 = around 0.08%
How do you open and close the douglas bag valve?
90 degrees clockwise to open and turn the valve 90 degrees anti-clockwise to close
What are normative values for a male?
Stage 1 of exercise: 120W
1.5kg x 80 rpm x 6 = 120W
Stage 2 of exercise: 160W
2.0 kg x 80 rpm x 6 = 160W
What are normative values for a female?
Stage 1 of exercise: 80 W
1.0kg x 80 rpm x 6 = 80W
Stage 2 of exercise: 120W
1.5kg x 80rpm x 6 = 120W
Whats the name of the standard table showing the caloric value of a litre of oxygen when used to oxidise mixtures of carbohydrate and fat?
zuntz table:
RER value of 1.00 = metabolising carbohydrate
RER value of 0.7 = metabolising fat
How do you work out work?
Force (kg) × Distance (meters/min) = Work (kgm/min)
What is cadence?
Revolutions per minute or RPM
What is the energy system involved?
Oxidative phosphorylation – glucose, free fatty acids, protein.